I've found an article about this car, maybe could clear a little bit more:
"Most people have a pretty firm handle on the history of the car they’re restoring, if only the basics – make, model, year of manufacture. These three basic chunks of information define a car and give it a place in autodom. But our friend Geoff Hacker has spent the last few years restoring a car of which he knows almost nothing.
If you attended the Amelia Island Concours d’Elegance this year and browsed through the Forgotten Fiberglass class that Geoff put together, you’d have come across the above car, which Geoff has labeled a “mysterion.” Not to be confused with Ed Roth’s Mysterion, Geoff has been using the term mysterion to encompass all the homebuilt fiberglass cars that he has yet to discover anything about. If you know Geoff and his terrier-like insistence on discovering every iota of information about a car he researches, then you have to wonder if any record still exists to fix these mysterions’ histories.
The mysterion displayed at Amelia belongs to Geoff’s friend Rick D’Louhy and is perhaps the most unusual of Geoff’s mysterions because he’s discovered two others exactly like it, which means that somebody tooled up and made an effort to put these fiberglass bodies into production, an enterprise that should have generated some paperwork and possibly a few magazine or newspaper articles. However, everything about the cars seems to have vanished except for the cars themselves.
Like many fiberglass cars of the early 1950s, these were built to set atop a 1940s Ford chassis, and this one gets its power from a dual-carbureted Ford flathead V-8 with Offenhauser heads. If you did inspect it at Amelia Island, you’d likely have noticed that it wasn’t quite finished at the time; Geoff passed along these photos and videos to note that its restoration is now complete – save for, of course, any idea about its history."